re: Best containers for making large blocks of ice

add a straw sticking out the top. The ice will climb the straw rather than expanding the sides.

I use the 32 oz Powerade bottles for big coolers - there shape is more uniform than atorade bottles. For a small cooler the 20 or 10 oz bottles are good. I like bottles so there isnt alot of water at the bottom when the ice melts,

If I dont care about the ice melting into water at the bottom of the cooler or whatever, large fast food cups are good. Fill a plastic one almost full, add a straw so it doens bust and freeze. Pop it out of the cup for a large ice cube. We used those all the time for water coolers to take to the ball fields or hay field.